By Andy Hargreaves

Monitoring a Manx shearwater burrow. Photo by Ed Marshall.

Monitoring a Manx shearwater burrow. Photo by Ed Marshall.

Highly unusual bird behaviour has been caught on camera on St Agnes.

Volunteers working on the Seabird Recovery Project, the plan to eradicate rats that prey on the birds’ eggs, have been using endoscope cameras to look down burrows for nesting Manx shearwater and storm petrels.

Scilly is one of only two breeding sites in England for the rare seabirds.

They’ve found a female incubating two eggs and it’s thought it could be the first time that’s been caught on camera.

Manx shearwater live for up to 55 years and normally lay a single egg each year.

It takes a lot of energy to raise a Manx shearwater chick, so they only lay one egg and the mother will go foraging far and wide for fish to feed their offspring.

The local team has asked seabird experts on Skomer and Lundy how this double nest could have happened.

They think that two females could have each laid an egg, but there’s been a squabble for the burrow and one female is now left incubating both of them.

Project Manager Jaclyn Pearson says they are watching and waiting to see whether the mum can raise both chicks.

The £900,000 project to eliminate the brown rat population on St Agnes and Gugh for at least a quarter of a century began in the autumn of 2013.

Jaclyn says that hopefully they will be able to declare the islands officially rat free next year.